In the Optical Assembly the incident radiance and irradiance are collected and split according to wavelength and focussed on the detector modules of the two optical channels. The Optical Bench consists of a single aluminium structure in which all elements are mounted. Attached to this aluminium structure are the two Detector Modules. The Optical Assembly Thermal Hardware consists of a thermal radiator and heaters. The thermal radiator is thermally connected to the detector modules via cold-fingers and flex-links. The heaters are attached to the Optical Bench structure and the CCD detectors.
In the figure below the optical layout of the visible channel is shown. Note that the orientation of the plane of drawing of this figure is perpendicular to that of the UV channel. The visible part of the spectrum (349 - 504 nm) is reflected by mirror (201) via folding mirror (202) to a collimating mirror (203). The rest of the visible channel consists of two folding mirrors (204 and 206), a plane grating with 1350 grooves/mm (207) and an objective (209 - 213) to image the diffracted beams on the second CCD detector.
Click on the figure for a larger view.